1. Field of the Invention
This invention relates to a patient simulator mannequin for use in training trauma medical personnel, physicians, and anesthesiologists, and more particularly to a realistic human eye simulator for a patient simulator mannequin that simulates pupil dilation and constriction responses to varying light levels, and eyelid control.
2. Description of Related Art
There are presently available patient simulator mannequins to train medical personnel in areas such as trauma treatment and anesthesiology. These mannequins typically have capabilities featuring spontaneous breathing and mechanical ventilation, thumb twitch, heart and breath sounds, pulses, and a complete airway anatomy for intubation and difficult airway training. Examples of anesthesiology simulator mannequins are disclosed in U.S. Pat. No. 5,403,192 to Kleinwaks et al., and in U.S. Pat. No. 3,520,071 to S. Abrahamson et al. (the '071 patent), the disclosures of which are incorporated herein by reference.
The traditional method of training in the medical profession involves proctoring where the student "learns by doing" at the elbow of an experienced person who guides and monitors the student's performance. This can put the patient at risk and limit the student's exposure to rare or critical events that do not occur very often. Using patient simulator mannequins, the student can develop skills in manual dexterity and diagnosis, recognize symptoms immediately, prescribe the right remedy, and correct the patient's condition, with none of the inherent risk.
Mannequins are particularly important for training in crisis management of critical events that happen rarely, especially in trauma and anesthesiology. The mannequins are typically computer controlled and be programmed for a variety of responses which simulate a variety of medical symptoms and problems. However, several human responses, such as independent eye pupil dilation and contraction, that are used to diagnose an actual patient's state, are lacking in the present simulators.
A bright light is used in trauma care to diagnose neurological injury or reaction to medication. In a patient with a properly functioning neurological system, the pupils should constrict when exposed to a bright light, and dilate again when the light stimulus is removed. In situations of neurological damage, or reaction to drugs and medication, the pupils of each eye may react differently to the same light stimuli.
Furthermore, a patient's state of consciousness is assessed by clues provided by the opening and closing of the patient's eyelids. Using present mannequins, which have no eye response, a complete patient exam, that would be conducted on an actual patient, is not possible.
Attempts have been made to provide simulator mannequins with eye response. For example, the '071 patent discloses a mannequin for use in anesthesiology training that provides limited eye response. The mannequin's eyelids open and close, and the simulated pupils dilate in a continuous change from normal to full dilation. Dilation of the pupils is provided by activation of a pneumatic actuator acting on a cam and cam follower to press a neoprene plunger into a plastic eye form. The harder the plunger is pressed by the actuator into the plastic eye form, the more the plunger's cone tip is flattened, thereby changing dilation diameters. However, there is no realistic eye response including no provision for individual control of the pupils and/or eyelids, or any response to a simulated patient state, or simulated patient physiology.
Hence, there exists the need for a realistic eye simulator to simulate human eye responses to a variety of stimuli, including normal and abnormal responses to a multitude of physiological conditions and drugs selected by the trainer. The eye simulator can be used, in combination with other simulated bodily responses, in patient simulator mannequins. Patient simulator mannequins, having a realistic eye simulator, can improve medical training realism using the mannequins because the responses of the mannequins would include eye responses that would normally be observed on an actual patient.